Xbee - practical range limit?

Hi,

Can anyone advise me on the practical range limit of a Xbee Pro 50mW? http://www.coolcomponents.co.uk/xbee-pro-50mw-module-with-whip-antenna-series-zb.html

The manual says 1 mile or 1600 meters, however, being a bit of cynic when it comes to manufacturers claims for their products I’d like to hear from someone who’s actually used one.

I’m in the UK, and I think 50mW is the max we’re allowed without a special license (50mW seems to be the highest any of the normal suppliers are prepared to sell)

My application is multiple aircraft communicating with a single base-station. The coms would be 90% air-to-ground and 10% ground-to-air. The bit rate would not need to be very high. The quoted range will be good enough for my application, but only if it’s true!

Anyone got any practical experience with them?

Thanks

Not I. Seems it'd be easy to test. Put one in a plane that replies with a simple message, and walk it across the airfield at ground level, and 10 feet up on a pole.

Seems it'd be easy to test

Yeah, I know, but the first thing I'd have to do is buy two units which may prove to be a waste of money!

My past (and somewhat limited) experience with radios is that to really get the feel of them you need to do a lot of testing in a lot of different conditions. A radio that works one day under one set of conditions may not work as well the next day if conditions change.

Cheers

The xbee pro series, around $40 a radio I think, are supposed to have good range from the digi.com website. We are looking into radios to use in a forest locale, range is really affected by frequency and the type of foilage it seems.